Unauthorized modification of displayed content in MDC SSO, SAP security note 1631953

SAP security note 1631953, "Unauthorized modification of displayed content in MDC SSO", is a program error note released on 08.11.2011. Below are the symptom, SAP recommended solution and the affected software components.

Description

Symptom

Multi Domain SSO cookie login can be abused by a malicious user, allowing them to modify displayed application content without authorization, and to potentially obtain authentication information from other legitimate users.

Solution

You can disable MDC functionality by removing the hosts that you have entered in the UME property ume.login.mdc.hosts. Then the SSO will only work within the domain (and possibly sub-domains depending on your configuration) where you initially log in.

For the real fix, please see the note’s Validity and Support Package Patches sections.

Reason and prerequisites

The MDC component within the Portal application does not sufficiently encode input parameters, resulting in a reflected cross-site scripting issue.

A reflected cross-site scripting attack can be used to non-permanently deface or modify displayed content from a website. Reflected cross-site scripting can be used to steal another user’s authentication information, such as data relating to their current session. A malicious user who gains access to this data may use it to impersonate the user and access all information with the same rights as the target user. If an administrator is impersonated, the security of the application may be fully compromised.

CVSS

Score 0

Affected components

• EPBC2 7.00 to 7.02
• EP-PSERV 6.0_640
• EP-BASIS 7.10 to 7.11
• EP-BASIS 7.20
• EP-BASIS 7.30
• EP-BASIS 7.31